In recent years, the number of portable telephone terminals which allow the user to transmit not only sounds but also images to another terminal during a telephone conversation on the portable telephone set and make the telephone conversation while the user sees the image transmitted from another terminal has increased.
Firstly, with the conventional portable telephone terminal having a function of sending not only sounds but also images to another terminal to allow a telephone conversation while the user sees images intended by another party during the telephone conversation on the portable telephone set, a function of sending a fictitious character image stored in the self portable telephone terminal to another terminal is also equipped.
The image transmitted to another terminal is the “image being taken by a camera outfitted with the portable telephone” or “fictitious character image stored in the self portable telephone terminal”.
This function includes transmission of different kinds of expressions or motion to the party at the other end where an image's expressions or motion is controlled by a key operation at the image sending side.
In this manner, the conventional portable telephone terminal has a function of switching the image data stored in the self portable telephone to be sent to the party at the other end in accordance with topics or feelings during telephone conversation, and a function of displaying the image data sent from the party at the other end.
Herein, a technique for confirming the feeling, convenience and intent of a caller at the time of call incoming has been proposed in which when a call originating operation of the portable telephone set is performed, an image selected by an image selection part is read from an image storage part, and sent to the destination by an image sending/receiving part, and when the image is received via the image sending/receiving part at the time of call incoming, the received image is displayed on an image display part before an off-hook operation of the portable telephone set is performed (e.g., refer to Patent Document 1).
Also, a technique for displaying character animation according to voices on the display screen of the portable telephone terminal in a relatively simple way has been proposed in which character data representing a character is stored beforehand in a storage part of the portable telephone terminal, a level of a received voice signal is detected, and animation of the character is displayed on an image display part in response to the voice level, whereby the character data is composed of sub-parts that are variation form of main parts of the character, the sub-parts are exchanged according to the voice signal level, and the character is activated by receiving a control signal of the character from the other terminal during telephone conversation (e.g., refer to Patent Document 2).
Patent Document 1: Japanese Patent Laid-Open No. 2004-015158
Patent Document 2: Japanese Patent Laid-Open No. 2005-064939
However, there are following problems with the conventional examples as described above.
To send the image to another terminal during telephone conversation, it is required to have an image sending/receiving part, which makes the configuration of the portable telephone complex, leading to increased current consumption. Also, it is required to have a transmission band at the time of transmitting the image, increasing a line transmission capacity.
Further, the operation for the user to send a control signal is troublesome, whereby it is required to display an operation screen to transmit an electronic mail even temporarily, and interrupt a part of the image enjoyed between the communication parties.